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arXiv · 2201.03337

Photo-induced Tellurium segregation in $\mathrm{MoTe_2}$

Takumi Fukuda·Ryota Kaburauchi·Yuta Saito·Kotaro Makino·Paul Fons·Keiji Ueno·Muneaki Hase
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Abstract

We report on the coherent phonon spectroscopy of polymorphic $\mathrm{MoTe_2}$ single crystals using a femtosecond-pulsed laser to investigate the relationship between structural phase transitions and photo-thermal effects induced by high-density laser excitation. Even when a femtosecond pulsed laser was used, which generally induces fewer heat accumulation effects than the case for a CW laser, tellurium segregation was observed in coherent phonon spectra with increasing excitation density, while no structural phase transition among polymorphs of $\mathrm{MoTe_2}$ was observed. The use of higher photon-energy excitation, however, was found to suppress tellurium segregation.

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Takumi Fukuda, Ryota Kaburauchi, Yuta Saito, Kotaro Makino, Paul Fons, Keiji Ueno, Muneaki Hase. 2022-01-10. Photo-induced Tellurium segregation in $\mathrm{MoTe_2}$. https://doi.org/10.1002/pssr.202100633

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